The present invention relates to the manufacture of disposable liquid-crystal-containing thermometers and, more particularly, to a method and means for producing and maintaining precise registration between the various layers and parts of the thermometer during manufacture.
Form-fill-seal machines are well known and commercially obtainable for the manufacture of blister packs wherein a product is packaged in a laminated carton usually of a transparent plastic facing with a backing layer of cardboard or such having any necessary identifying printing thereon. Such machines generally operate in such manner that the formed blisters of plastic are intermittently fed in a continuous web, and are filled while advancing with a product such as a number of tablets. After filling, the package is closed by heat-sealing the printed backing, also fed as a continuous web, onto the blister facing. The formed cartons are punched out of the laminated web and conveyed away while the remaining web material is wound onto a salvage mechanism.
Ordinarily, a great deal of precision in disposing and attaching the various components of the pack is not required in such machines. Thus, articles requiring precise positioning of the components during manufacture cannot be readily produced on such machines.
The present invention is directed to providing a form-fill-seal type machine which can be used to manufacture precision laminated products and in particular, disposable liquid-crystal-containing thermometers.